1. Field of the Invention
This invention relates to a home base modem system in a wireless communication system that provides telephone, data and Internet connectivity to a plurality of users.
2. Description of Related Art
Several systems are currently in place for connecting computer users to one another and to the Internet. For example, many companies such as Cisco Systems, provide data routers that route data from personal computers and computer networks to the Internet along conventional twisted pair wires and fiber optic lines. These same systems are also used to connect separate offices together in a wide area data network.
However, these systems suffer significant disadvantages because of the time and expense required to lay high capacity communications cables between each office. This process is time consuming and expensive. What is needed in the art is a high capacity system that provides data links between offices, but does not require expensive communication cables to be installed.
Many types of current wireless communication systems facilitate two-way communication between a plurality of subscriber radio stations or subscriber units (either fixed or portable) and a fixed network infrastructure. Exemplary systems include mobile cellular telephone systems, personal communication systems (PCS), and cordless telephones. The objective of these wireless communication systems is to provide communication channels on demand between the subscriber units and the home base in order to connect the subscriber unit with the fixed network infrastructure (usually a wired-line system). Several types of multiple access systems currently exist for wirelessly transferring data between multiple sites. For example, wireless communication systems have typically used a Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA) or Frequency Division Multiple Access (FDMA) type system to facilitate the exchange of information between two users. These access schemes are well known in the art.
Often in these wireless communication systems a modem is used for modulating and demodulating the information that is exchanged between users. Inside the modem circuit an equalizer is employed to correct distortions either in the wireless channel or fix imperfections in the analog circuitry. A novel equalizer with enhancements to improve performance especially using higher order QAM modulation is described herein.